Custom Filter Types - C1 ASP.NET MVC

// This file locates: "Scripts/Lesson/C1FlexGrid/CustomFilterTypes.js".
c1.documentReady(function () {
    var theGrid = wijmo.Control.getControl('#theGrid');
    var filter = c1.getExtender(theGrid, "theGridFilter");
 
    // filter only by condition (not by value)
    filter.defaultFilterType = wijmo.grid.filter.FilterType.Condition;
 
    // remove sort buttons
    filter.showSortButtons = false;
});

using System.Web.Mvc;
 
namespace LearnMvcClient.Controllers
{
    public partial class C1FlexGridController : Controller
    {
        // GET: CustomFilterTypes
        public ActionResult CustomFilterTypes()
        {
            return View(Models.FlexGridData.GetSales(200));
        }
    }
}

@model IEnumerable<FlexGridData.Sale>
 
<h1>
    @Html.Raw(Resources.C1FlexGrid.CustomFilterTypes_Title)
</h1>
<p>
    @Html.Raw(Resources.C1FlexGrid.CustomFilterTypes_Text1)
</p>
<p>
    @Html.Raw(Resources.C1FlexGrid.CustomFilterTypes_Text2)
</p>
@(Html.C1().FlexGrid().Id("theGrid").Height(250)
    .AllowSorting(false)
    .Bind(b => b.Bind(Model).DisableServerRead(true))
    .Filterable(f=>f.Id("theGridFilter"))
)